The invention relates to an inhalant medicator suitable to prescribe granulated medicines toward within lungs of a patient by way of breathing action of the patient.
Generally, there are two typical medications of prescribing granulated medicines toward within lungs of an asthmatic patient, that is, one being a medication that the granulated medicines are inhaled by way of a liquid aerosol atomizer, and the other being an inhalation treatment that very fine granular medicines encapsulated in a capsule, such as granules each having a particle diameter ranging from 5 xcexcm to 10 xcexcm, are inhaled by breaking through the capsule. Of these medications for an asthmatic patient, an inhalant medicator, used for the latter inhalation treatment where encapsulated granulated medicines are inhaled, has been disclosed in Japanese Patent Provisional Publication No. 8-47531.
The conventional inhalant medicator disclosed in the Japanese Patent Provisional Publication No. 8-47531 is generally comprised of a medicator body equipped at one axial end with a capsule housing area and at the other axial end with an inhalant port, an inflow air passageway having an axial inflow passage extending in the axial direction of the medicator body and a pin insertion channel extending in a radial direction of the medicator body for communicating the capsule housing area with the atmosphere, an outflow air passageway having an outflow passage extending in the axial direction of the medicator body and a pin insertion channel extending in the radial direction of the medicator body for communicating the capsule housing area with the inhalant port, and a boring tool having pins insertable toward the capsule through the respective pin insertion channels for breaking through the capsule accommodated in the capsule housing area.
In conventional inhalant medicator, when breaking through a capsule accommodated in the medicator body by way of a boring tool, a hole necessary to secure a required area of a flow passage to be created between the interior of the capsule and the pin insertion hole is formed in the capsule by inserting the pins toward the capsule along the respective pin insertion channels and by pricking or punching holes in the capsule with the pins.
Hereunder briefly explained is the inhalation treatment achieved by the previously-noted inhalant medicator. First of all, as a preparatory operation of the inhalant medication, a capsule filled with granular medicines is enclosed or fitted in the capsule housing area. Under this condition, the pins of the boring tool are moved in the respective pin insertion channels and guided towards the capsule. This permits the pins to penetrate or pierce the capsule in the radial direction of the capsule, thus forming holes pierced in the capsule and communicated with the respective pin insertion channels. Thereafter, the patient draws his or her breath while taking the inhalant port in his or her mouth in order to dose the patient with the granulated medicines stored in the capsule. This produces air flow through the axial inflow passage and the pin insertion channel included in the inflow air passageway toward within the capsule. The air flow agitates the granular medicines stored in the capsule, and flows out of the capsule together with the agitated granular medicines. The mixture of the incoming air and the granular medicines is then carried into the inhalant port through the pin insertion channel and the outflow passage included in the outflow air passageway. In this manner, the granular medicines flowing out of the capsule can be inhaled into the lungs of the patient.
In conventional inhalant medicator as discussed above, the formation of holes is achieved by punching or piercing holes in the capsule with pins. Therefore, there are slight fluctuations in hole sizes when forming holes in the capsule. Such slight fluctuations of the hole size result in variations in the fluid-flow passage area between the interior of the capsule and the pin insertion hole. A flow velocity and a flow rate of the air flowing through the internal space of the capsule are both regulated depending on the flow passage area of the hole penetrated by the pin. For the reasons set out above, during medication with a granular medicine having a strong condensation property, there is a problem of unstable dispersion of the granular medicine, thus preventing the granular medicine from being inhaled toward within lungs of a patient stably and satisfactorily at all times where medications are repeatedly made with medicines of different condensation properties.
It is, therefore, in view of the previously-described disadvantages of the prior art, an object of the present invention to provide an inhalant medicator which is capable of stably dispersing granulated medicines, while satisfactorily keeping a specified flow velocity and a specified flow rate of air flowing through the interior of a capsule pierced during medication.
In order to accomplish the aforementioned and other objects, according to the invention as claimed in claim 1, an inhalant medicator comprises a medicator body formed at one axial end with a capsule housing area and at another axial end with an inhalant port, an inflow air passageway having an inflow passage extending in an axial direction of the medicator body and a first pin insertion channel extending in a radial direction of the medicator body for communicating the capsule housing area with the atmosphere, and an outflow air passageway having an outflow passage extending in the axial direction of the medicator body and a second pin insertion channel extending in the radial direction of the medicator body for communicating the capsule housing area with the inhalant port, a boring tool having pins insertable toward a capsule through the first and second insertion channels for pricking holes in the capsules accommodated in the capsule housing area with the pins, and a flow-control orifice means disposed in a first air passageway of the inflow and outflow air passageways and having a flow passage area less than a flow passage area of each of the channels and less than a flow passage area of a second air passageway of the inflow and outflow air passageways. In the inhalant medicator made according to the invention defined in claim 1, the flow velocity and the flow rate of air flowing through the inflow air passageway, the capsule and the outflow air passageway can be adjusted or controlled by the flow-control orifice means having the flow passage area less than the flow passage area of each of the holes pricked or pierced in the capsule with the pins and less than the flow passage area of the second air passageway. Thus, the air of a specified flow velocity and a specified flow rate is able to stably and satisfactorily flow through the interior of the capsule, irrespective of fluctuations in the hole size of each of the holes pricked in the capsule.
According to the invention as claimed in claim 2, in order to provide the flow-control orifice means of the inhalant medicator, one air passageway of the inflow and outflow air passageways is formed as a flow-constriction passageway having a flow passage area less than the flow passage area of each of the holes pricked in the capsule with the pins. In the inhalant medicator made according to the invention defined in claim 2, the flow-constriction passage, having the flow passage area less than the flow passage area of each of the holes pricked in the capsule and less than the flow passage area of the second air passageway, is able to effectively adjust or control the flow velocity and the flow rate of the air flowing through the interior of the capsule.
According to the invention as claimed in claim 3, an orifice plate is fitted to the medicator body and located in at least one of the inflow and outflow air passageways, and the flow-control orifice means of the inhalant medicator is constructed by an orifice, formed in the orifice plate in a manner so as to communicate with the at least one of the inflow and outflow air passageways to control the air flow passing through the interior of the capsule by way of orifice constriction. That is to say, in the inhalant medicator made according to the invention defined in claim 3, the orifice plate, having a flow passage area less than the flow passage area of each of the holes pricked in the capsule, can adjust or control the flow velocity and the flow rate of the air flowing through the interior of the capsule.
According to the invention as claimed in claim 4, an orifice plate is located in at least one of the inflow and outflow passageways, and the flow-control orifice means of the inhalant medicator is constructed by a plurality of orifices having flow passage areas different from each other, and formed in the orifice plate in a manner so as to selectively communicate with the at least one of the inflow and outflow air passageways to optimally control the air flow passing through the interior of the capsule in accordance with a selectable orifice constriction. In the inhalant medicator made according to the invention defined in claim 4, depending upon switching between the plurality of orifices having different orifice-constriction characteristics, the flow velocity and the flow rate of the air flowing through the at least one of the inflow and outflow air passageways can be variably adjusted or controlled. That is, the best orifice size is selectable from the plurality of orifices, depending on physical properties of medicines enclosed in the capsule. This ensures stable dispersion of the medicines.
According to the invention as claimed in claims 5 and 6, the medicator body of the inhalant medicator is formed with an axial auxiliary air passage axially penetrating the medicator body in circumferentially spaced relationship with both the inflow passage and the outflow passage. Additionally, an auxiliary orifice is formed in the orifice plate as claimed in claims 3 and 4, for adjusting a flow passage area of the axial auxiliary air passage. As can be appreciated, the orifice plate is selectable from a plurality of orifice plates each of which is different from the other in auxiliary orifice size. In the inhalant medicator made according to the invention defined in claims 5 and 6, the best auxiliary orifice size is selectable depending on an adult of a large vital capacity, a child of a small vital capacity, a strong chest, or a weak chest. Thus, the auxiliary air quantity can be optimally adjusted or controlled by way of the auxiliary orifice formed in the orifice plate. The sole orifice plate may be formed with a plurality of auxiliary orifices spaced angularly circumferentially spaced from the previously-noted plurality of orifices and having flow passage areas different from each other, so as to selectively communicate with the axial auxiliary air passage formed in the medicator body. Thus, in the inhalant medicator equipped with the orifice plate having the plurality of auxiliary orifices of different auxiliary orifice sizes as well as the plurality of orifices of different orifice sizes, the flow velocity and the flow rate of the air flowing through the interior of the capsule can be variably adjusted or controlled and simultaneously the flow rate of auxiliary air is selectable depending on a vital capacity of a patient and a strong or weak breathing action of the patient.